Were you booking for May or early June? Isn't that possible because Pandora FP+ were just recently released and there are actually some people who don't scour Disney sites to learn about release dates for FP+?
I am just saying that, in my experience, when Disney releases FP+ and/or dining reservations outside the normal time frames (less than 60 days out for FP+ and less than 180 days out for dining reservations), they are usually much easier to get because a lot of people who make reservations don't keep checking sites to find out when things are newly released (gasp! Who are these people??

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It is certainly possible that Pandora attractions will remain easier to get than the other two, but it will be interesting to see what happens once those who are booking FP+ can actually book Pandora attractions a full 60 days in advance.
Could also be that, since these are two new attractions in one park with a tiered system, that is dividing up the FP+ more evenly. With Frozen, everyone is booking it because it is by far the newest thing in Epcot, and it has a particularly low capacity and a slow loading time.
Also, with Disney having these fantastic late night EMH hours from 11-1 for Pandora, it seems like it should be pretty easy to experience both of these attractions- even without a fastpass. Most guests with children under 10 are out of the parks by 11. I love late nights in the parks.